the Messenger of Allah ﷺ passed judgment on the basis of an oath (from the claimant) along with a (single) witness. [This is in the absence of two witnesses.] (Using translation from Ibn Mājah 2368)

أَنَّ رَسُولَ اللهِ ﷺ قَضَى بِالْيَمِينِ مَعَ الشَّاهِدِ